1. Field of the Invention
The present invention relates to an optical receptacle and a manufacturing method thereof. In particular, the present invention relates to an optical receptacle suitable for performing optical communication using optical fiber, and a manufacturing method thereof.
2. Description of the Related Art
Since the past, an optical module component referred to as an optical receptacle has been used in optical communication using optical fiber. The optical receptacle is configured such that an end of an optical fiber, held within a cylindrical ferrule, is inserted with the ferrule into the optical receptacle and fixed. In addition, an optical element, such as a semiconductor laser, can be attached to the optical receptacle. The optical receptacle, onto which the optical element and the optical fiber are mounted in this way, optically couples the optical element and the optical fiber.
As an example of an optical receptacle such as this, an optical receptacle is used that includes a lens and a fiber stub on an optical path between the optical fiber and the optical element. The optical receptacle allows light emitted from the optical element to pass through the lens or the fiber stub and couples the light onto the end face of the optical fiber.
An optical module including an optical receptacle of this type is required to have good wiggle characteristics.
Here, wiggle characteristics refer to load characteristics of optical coupling efficiency, indicating changes in the optical coupling efficiency of the optical element and the optical fiber depending on load, when, in a state in which the end of the optical fiber is inserted with the ferrule into the optical receptacle and the optical element is attached to the optical receptacle, load is applied to the ferrule in a direction perpendicular to an optical axis of the end of the optical fiber.
Good wiggle characteristics indicate that deterioration of optical coupling efficiency is low, regardless of increase in load.
In addition to the optical module being required to have good wiggle characteristics, an optimal configuration is required of the optical receptacle itself to achieve good wiggle characteristics.
Here, it is known that the wiggle characteristics improve as the rigidity of the optical receptacle increases. A conventional configuration using an optical receptacle made of metal having high rigidity is suitable in terms of achieving good wiggle characteristics.
However, the metal optical receptacle has a disadvantage of being unsuited for mass production due to high material cost.
Therefore, since the past, there has been a demand for achieving an optical receptacle that can actualize good wiggle characteristics at a low cost. To meet such demands, various proposals have been made.
For example, the optical receptacle is formed using an inexpensive resin material. Rigidity of the optical receptacle is increased in part by a separate sleeve made of a material with high rigidity (such as zirconia) being inserted into a section of the optical receptacle in which the ferrule is inserted, and the sleeve being fixed by adhesion.    Patent Literature 1: Japanese Patent Laid-open Publication No. 2006-184338
However, because the sleeve is conventionally fixed to the optical receptacle by adhesion, problems occur in that the adhesion procedure is costly, and manufacturing efficiency is poor.